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Hydrochemical analysis of the high-salinity lakes in the Ishim Plain (>250-300 g/L) located at the border with the Northern Kazakhstan uranium ore province is performed. The studies have shown that the main factor of concentration and redistribution of uranium in the lake basins of the Ishim Plain are the processes of intense salt deflation causing sanding of lakes and uranium depletion in the near-surface layer of the bottom deposits. The correlation between the hydroxide forms of uranium binding in the bottom lacustrine deposits of the Ishim Plain and the coffinite composition of the Semizbai deposit makes it possible to consider this province to be promising for the discovery of hydromineral uranium deposits. [ABSTRACT FROM AUTHOR]

Objective: Stroke is a severe complication of type 2 diabetes mellitus. Glucagon-like peptide-1 receptor agonists have been shown to have a neuroprotective effect in experimental diabetes. The aim of this study was to determine if their neuroprotective effect is an independent property of the drug independent of glycaemic control., Methods: This two-phase study used male Wistar rats. In the first phase, experimental animals were pretreated with liraglutide, while controls received only vehicle. After transient focal brain ischaemia modelling, neurological deficit and brain infarct volume were measured. In the second phase, the first and the second groups of experimental animals with type 2 diabetes mellitus received liraglutide and metformin, respectively, while control animals with diabetes received only vehicle. After transient focal brain ischaemia modelling, neurological deficit and brain infarct volume were evaluated., Results: Pretreatment with liraglutide in diabetic and non-diabetic animals reduced infarct size as compared to controls, while only non-diabetic liraglutide-treated rats presented neurologic deficit decreases. Despite glycaemia normalization, metformin-treated diabetic rats had no differences in stroke outcome when compared to the control group., Conclusion: The neuroprotective effect of liraglutide is not associated with glycaemic control amelioration in experimental type 2 diabetes mellitus.

The aim of this study is to evaluate the definition of water chemical type, with particular attention to soda brine characteristics by assessing ionic composition and pH values on a large geographic scale and broad salinity (TDS) range of Eurasian inland saline surface waters, in order to rectify the considerable confusion about the exact chemical classification of soda lakes and pans. Data on pH and on the concentration of eight major ions were compiled into a database drawn from Austria, China, Hungary, Kazakhstan, Mongolia, Russia, Serbia, and Turkey. The classification was primarily based on dominant ions exceeding an equivalent percentage of 25 (> 25e%) of the total cations or anions, and the e% rank of dominant ions was also identified. We identified four major types: waters dominated by (1) Na-HCO3 (10.0%), (2) Na-HCO3 + CO3 (31.4%), (3) Na-Cl (45.9%), and (4) Na-SO4 (12.7%), considering only the first ion by e% rank. These major types can be divided into 30 subtypes in the dataset, taking into account the e% rank of all dominant ions. The major and subtypes of soda brine can be divided into "Soda" and "Soda-Saline" types. "Soda type" when Na+ and HCO3- + CO3(2-) are the first in the rank of dominant ions (> 25e%), and "Soda-Saline type" when Na+ is the first in the rank of dominant cations and the sum of HCO3- + CO3(2-) concentration exceeds 25e%, but it is not the first in the rank of dominant anions. Soda-saline type can be considered as a separate evolutionary stage between Soda and Saline types respect to the geochemical interpretation by saturation indexes of brines. The obtained overlapping ranges in distribution demonstrate that a pH measurement alone is not a reliable indicator to classify the permanent alkaline "soda type" and various other types of temporary alkaline waters., Competing Interests: The authors have declared that no competing interests exist.

The purpose of this study was to identify the prevailing chemical composition and trophic state of the shallow saline steppe lakes of North Kazakhstan along a wide size range (< 1-454 km 2 ) and salinity gradient (2-322 g L -1 ) on a large spatial scale (1000 km), taking into account the potential effects of human disturbances. Water depth, Secchi disk transparency, temperature, pH, electric conductivity, major ions, total dissolved solids, total organic carbon, total nitrogen and phosphorus, nitrate, soluble reactive phosphorus, and chlorophyll a were measured. The equivalent percentage of major ions, Spearman rank correlation, multivariate analyses, equilibrium state of lakes, and spatial GIS autocorrelation were calculated. The impact of human disturbances (settlements, farms, and mines) on total organic carbon, nitrogen, phosphorus, and chlorophyll a were tested by Kruskal-Wallis ANOVA. The most common combinations of dominant ions were Na-Cl>SO 4 and Na-Cl (n = 16; 64%); the Ca, Mg, HCO 3 , and SO 4 ions precipitate with increasing salinity (2-322 g L -1 ); and ion composition shifts from Na>Mg-Cl>SO 4 to Na-Cl. The most of the chemical variables positively, but chlorophyll a negatively, correlated with total dissolved solids, and the total phosphorus had no significant correlation with any variables. The trophic state of these lakes in most cases exceeded the hypertrophic level. The increase in salinity causes change in chemical composition and effects on the phytoplankton development independently from the size of water surface, and the human disturbances had negligible effect on the trophic state of shallow saline lakes in this region of Kazakhstan.

We have examined the development of medication-related osteonecrosis of the jaws (MRONJ) in rats with no previous accumulation of zoledronic acid in the mandible. Ten male Wistar rats (weight 350-400g) were anaesthetised with chloral hydrate 450mg/kg intraperitoneally and the first and second mandibular molars on the left side were extracted. The five experimental rats were given six injections of zoledronic acid 0.18mg/kg over the next four weeks (total dose 1.08mg/kg). Two injections were given at once as an intravenous bolus injection (0.36mg/kg). Then rats were given 4 injections (0.18mg/kg) with 1 week interval over the next four weeks, after which they observed for a further four weeks. The five control rats were injected with saline. At the end of the eighth week, the animals were killed by asphyxiation in a carbon dioxide chamber, and their bone structure was visualised using cone-beam computed tomography (CT) and Galaxis software. We then studied the mandibles histopathologically to investigate the incidence of necrosis and infiltration of inflammatory cells. The cone-beam CT images in the experimental group showed deficiencies in the bone structure in the extracted molar area of the lower alveolar ridge. The histological findings in the mandibles of the group given zoledronic acid showed necrosis and infiltration of inflammatory cells, which were not present in the control group. We conclude that the immediate effect of zoledronic acid on the bone tissue during regeneration is an important factor in the development of MRONJ, in addition to the previously reported effects of the duration of treatment with zoledronic acid., (Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.)

In the review mechanisms of protective action of a hyperthermia, light and low-intensity ultrasonic radiation are considered. These physical factors don't cause oxygen starvation, however promote the increase of organ's tolerance to an ischemia/hypoxia. On materials of original articles the analysis of preconditioning mechanisms cause by high temperatures, low-intensive ultrasonic and laser irradiation was carried out at ischemia. By comparison of processes in tissues at influence by physical factors the general triggers--active forms of oxygen (O2*, H2O2, HO*) were revealed.

The aim of this review was the discussion of creatine involvement in metabolism of nervous tissue cells. The questions of creatine penetration through the blood brain barrier and creatine transporter expression were raised. Also mechanisms of creatine protective effect were considered at experimental models of brain ischemia. It was shown that creatine was involved in energy metabolism (creatine phosphate synthesis), inhibition of excitotoxicity. Besides it had antioxidant and antiproliferative effects. The creatine delivery problem was also discussed. Synthesis of substances capable to get through the blood brain barrier without CRT was the possible solution of the problem. The most perspective substances were creatine amides apparently capable to move through cell membranes without amino acid transporters. Prospects of their application were discussed.

The aim of the study was to investigate neuroprotective effect of creatine glycine ethylic ether fumarate (creamide). The methods involved intragastric administration of creamide in doses of 30 and 50 mg/kg twice a day for 10 days. Focal 30 minutes cerebral ischemia model by endovascular suture occlusion of the middle cerebral artery in a rat with subsequent reperfusion period for 48 hours was produced. Assessment of creamide stability in gastric juice was performed. Ischemic lesion volume accompanying focal ischemia was visualized and determined. Similar infarction patterns had been found with histological methods. Garcia scale was used for clinical study of neurological deficit in rats. Our data suggest a significant neuroprotective effect of creamide in dosage 50 mg/kg administered twice a day which decreased brain lesion volume produced by ischemic and reperfusion injury.

The influence of creatine or its derivates on the cell energy potential may be one of the possibl approaches to induce neuroprotection. Effect of creamide (creatinylglycine ethylic ether fumarate) on the brain injury was studied in the experimental model of the brain ischemia/reperfusion in rats. The experiments were carried out in 14-20 weeks old male Wistar rats weighing 240-300 g, anesthetized by chloral hydrate (430 mg/kg). Creamide was administered intravenously at the doses of 50, 70, 140, and 280 mg/kg. For comparison phosphocreatine was used at the dose of 255 mg/kg. Creamide and phosphocreatine were administered intravenously (in volume of 1 ml within 5 min) 30 min before cerebral middle artery occlusion. Focal cerebral ischemia for 30 min was produced by endovascular suture occlusion with the subsequent 48 h reperfusion period. Creamide administration resulted in dose-dependent decrease of brain ischemic injury. Creamide administered at the doses of 140 and 280 mg/kg was more effective as compared with phosphocreatine (255 mg/kg). The data obtained open new perspectives for further research and development of new creatine-derived drugs with neuroprotective action.

Using clamp method it had been shown that He-Ne laser irradiation of the snail neurons increases the amplitude of voltage-gated slow potassium currents in dose of 0.7 x 10(-4) (fluence 1.5 x 10(2) Wt/m2) and decreases it in dose 0.7 x 10(-3). Bupivacaine and lidocaine suppressed potassium currents. Laser irradiation in dose 0.7 x 10(-3) enhanced the inhibitory effect of bupivacaine (10 mcM) and in dose 0.7 x 10(-4) it decreased the inhibitory effect of bupivacaine. The results of the study suggest mechanisms of the He-Ne laser irradiation effect in combination with pharmacological substances on ion channels of electrically excitable cells.

The aim of this work was to investigate the myocardial protection against ischemia/reperfusion using low level laser irradiation (LLLI). It has been shown that pulse pressure was higher in the period of post-ischemic reperfusion as compared with the control group. It provided a better restoration of myocardial contractility as well as increasing of coronary flow in the reperfusion period. The amount of ventricular rhythm disorder episodes decreased. These effects of laser application were registered in conditions of coronary flow reduction less than 50%. One of the suggested mechanisms of laser effect is an ATP-sensitive channel activation.